Single-valve four-cycle explosive-engine.



J. KEISTER.

SINGLE VALVE FOUR-CYCLE EXPLOSIVE ENGINE.

APPLICATION FILED JAN. 30, 1914.

1, 144,208 Patvntcd June 22, 191;").

2 SHEETS--SHEETI Ticrl.

WITNESSES V IIVVE/WQR k izflzu Zfzlvier ATTORNEYS J. KEISTER.

SINGLE VALYE FOUR-CYCLE EXPLOSIVE ENGINE- APPLICATION FILED JAN. 30. I914.

1 1%,2@8g Patented June 22, 1915.

2 SHEETSSHEET 2- firms? Eddie? By A TTORNEYS J'AHEiKEISTER, 0F STEUBENVILLE, OHIO.

SINGLE-VALVE d'OmCYCLE mLOSIVE-ENGINE.

' Bpeeiflcation of Letters Patent.

Patented June 22, 1915.

Application filed January 30, 1914. Serial No. 815,427.

To all whom it may concern:

Be it known that I, J nuns Knrs'rnn, a citizen of the United States, and a resident of Steubenville, in the county of Jefferson and State of Ohio, have invented a new and I'mplroved Single-Valve Four-Cycle Explosivengine, of which the following is a full, clear, and exact description.

This invention relates to four-cycle engines of the single valve type in which the valve is in the form of a. sleeve or tube having separate inlet and exhaust'ports adapted to register respectively-with the inlet'and exhaust ports of the c linder during the suc tion and exhaust stro es of the iston, said valve havin one stroke back and forth with each cycle 0 the engine.

The present invention relates to improvementsf to engines of the type referred to, and more esiecially to the va ve operating mechanism own in my rior applications for Letters Patent Serial Number 7 70,347, of May 28, 1913, and Serial Number 802,917, ofNovember 25, 1913.

In my prior valve operating mechanisms a lever mounted in the crank case is linked to the valve of the enginefand the lever carries a roller which rides on an operating cam in engagement with which the roller 1s maintained by a spring acting in conjunction with the cam to reciprocate the valve. This construction is effective for certain engine sgeeds but for very high speeds it is not as e ective as desired because of the momentum of. the moving parts bein too great to be opposed by the spring, an to overcome this by tightening the spring results in com plications due to the high pressure and friction on the journals of the roller.

The general objects of the present invention are to provide a simple and effective valve operating mechanism especially adapted for high speed engines, although it is suitable or engines operating at a low speed, suchvvalve mechanism embodying a air of synchronously rotating complemenroller on the ever, wh ch roller is of substantial dimensions, while the radii of the cam are reduced to a minimum for the pur' pose of preventing an excessively high eripheral speed thereof, which, together with the large roller, is conducive to long life, efiicient operation and noiselessness;

With such objects in view, and others which will appear as the description proary cams. an aging opposite sides of the.

ceeds, the invention comprises various novel features of construction and arrangement of parts such as will be set forth with particularlty in the following description and claims appended hereto.

In the accompanying drawings, which illustrate one em odlment of the invention, and wherein similar characters of reference indicate corresponding parts in both the views, Figure 1 is a longitudinal'section oi an engine of the type referred to and equi pad with the improved valve operating mec anism; and Fig. 2 is a diagrammatic view of the cams and roller.

Referrin to the drawing, A desi ates a cylinder 0 any approved construction having an inlet port 1 and an exhaust ort 2 preferabl at opposite sides, and sliding in the cylin er is a sin le cylindrical or tubular valve B that iscare 11y finished as the piston C reciprocates therem, there being an inlet port 1 in the valve and an exhaust port 2, these ports being so arranged that on the down or out stroke of the valve the port 2 first registers with the port 2 so as to allow the fired gases to exhaust during the exhaust stroke, while the port 1 registers with the port 1 during the suction stroke of the piston, and on the return stroke of the valve the inlet ports first close and then the exhaust ports quickly close, so that on the in or up stroke of the piston C the charge will be compressed, it being understood that this quick closing movement of the exhaust ports occurs while the piston C is moving very slowly from its dead center, and hence only a negligible uantity of fuel mixture can escape out of t e exhaust ports during this passage of the valve port 2 across the cylinder port 2..

The valve B extends into the crank case D and is connected by the link 3 with. a lever 4 that is fulcrumed at one end 5 to one side of the crank case and extends across the piston rod 6 to the opposlte slde,

has reference to the contour or peripheral shape thereof, and the cams are so shaped that both will always be in contact with the roller and cause the latter to move up and down in a curvilinear path about the lever 4; as a center, and consequently the lever \vill oscillate and reciprocate the valve B. The cams may be divided into four quarters (1., b, c and d for the upper cam, as shown in Fig. 2, and a, b, c and d for the lower cam, the section a of the upper cam corresponding to the section a of the lower cam, and so on; and furthermore these quarter sections correspond respectively to the exhaust, suction, compression and expansion strokes in the cycle of the engine. Since the cams are complementary the sum of the two radii thereof that are effective at any time in engaging with the lever roller 7, is equal to the sum of the radii engaging the roller at all the revolution of the cam, so that t ere will be no loose play, and one cam is always active in moving the roller up or down, while the other cam is receding. Or, in other words, one cam is an actuator at one instant and the other cam is the actuator at another instant, and the only time the cams are not moving the roller up and down is when the valve is 'idle, as, for instance, when its ports are registering with the corresponding ports of the cyhnder. Considering the movement of the valve with respect to the cam 10, Fig. 2, the roller is engaging the portion of the cam of smallest radius, and consequently the valve will be in its uppermost or closed position. This is the position of the valve at the beginning of the explosion stroke of the piston, and during the working stroke of the iston the portion 11 of the cam rides over the roller and moves the lever, and hence the valve,

downwardly, so that the exhaust port of the valve will register with the exhaust port of the cylinder when the portion 12 of the cam reaches the roller. The spent gases are now forced out during the major part of the exhaust stroke and toward the end of this stroke the eccentric part 13 of the cam engages the roller 7 and moves the lever and valve still farther downwardly, whereby the exhaust ports close and the inlet port 1" of the valve registers with the inlet port 1 of the cylinder, and now the part 14 of the cam holds the valve stationary during a considerable part of the suction stroke, when finally the decidedly eccentric part 15 of the cam rides over the roller and allows the lever to be moved upwardly by the lower cam very rapidly, so that the ,inlet port-will close and the exhaust port of the valve quickly pass the exhaust port of the cylinder. Theniston now compresses the charge which is duly fired and the cycle of operation repeated.

oints in exhaust and inta It is obvious with the cam construction shown that the engine-can have a very high speed, and yet the valve will always be positively operated without any lost motion,.

and at the same time wear and friction are reduced to a minimum.

From the foregoing description taken in connection with the accompanying drawings, the advantages of the construction and method of operation will bev readily understood by those skilled in the art to which the invention appertains, and while I have described the apparatus which I now consider to be the best embodiment thereof, I desire to have it understood that the apparatus shown is merely illustrative and that mechamsm for moving the valve two steps in one direction to first open the exhaust port and then open the inlet port wh1le clos- 'mg the exhaust port, and one step in the .op-

posite direction to close both rts, sald mechanism consisting of a pair 0 three step complementary cams synchronousl driven, a lever linked to the valve and a r01 er thereon engaging the said pair of complementary cams, each cam having an eccentric portion for reciprocating the valve in one continuous stroketo close both ports, a concentric portion for holding the valve to remain closed during the major arts of the compression and expansion stro es ofthe piston, an eccentric portion for moving the valve to open the exhaust port, a concentric portion for holding the valve in open-exhaust-port position, an eccentric portion for moving the valve still farther to close the exhaust port and open the inlet ort and a concentric portion for holdingt e valve in inlet-portopenposition, the sum of the efiective radii of the cams ateveryinstant being constant. 2. A four cycle; explosive engine including a single sucti'onjand'exhaust valve having an intermittent stroke in one direction to suecessively open an exhaust and a suction port and a continuous stroke in the other direction .for intercepting communication with e ports on its return movement, an element connected with the valve for reciprocating the same, and a pair of synchronously rotating complementary cams, each having three concentric portions of different radil and eccentric portions so related In testimony whereof I have siped my name to specification in the presence of two subscribing witnesses.

J AMES KEISTER.

Witnesses F. C. Pew

JOHN R. Karin. 

